luke lazarus was convicted of raping an 18-year-old at soho nightclub .
lazarus was sentenced to a minimum of three years in jail on march 27 .
he is the son of the sydney venue 's owner andrew lazarus .
the photo was posted on april 3 to promote soho 's easter club event .
soho management told daily mail australia the image was uploaded by an ` external promoter ' who they had given access to their facebook page .
the club agrees that the image used was ' 100 per cent inappropriate '